Really Bad cramps!!!???

I have tried everything but pain medicine because i can not drive while taking them. But anyways... I have been getting ridiculouslyy horrible cramps. I am 21 years old and have been on birth control for 6 years for this very reason. But they are coming back and worse. i made a doc apt for Jan. 23. I was told from Doc that the BC will help them not be so severe and they have before but not now. any ideas of why they are getting bad again. Also im on yasmin thats the strongest and worse BC out there!